关于数据库中查询一个字段疑惑

[Bincker]

环境：
windows2003
SqlServer2005
数据库：30个库
表和字段数不清

想查询一个用户的数据，想查询的用户叫 “小王”，而我不知道这个 “小王” 在哪个库里面的哪个表的字段里。
只知道这个小王在这个数据库服务器上的某一个库德某一个表的某一个字段中。

1.请问我有什么办法能找到这个“小王”的具体哪个表的位置呢？

2.请问如果我要是知道 这个“小王”在 username 这个字段，我该怎么找到他的库和标段？

3.请问如果我现在知道了这个“小王”在哪个库，并且知道了字段名字为 username，我该怎么找到这个表？

谢谢../ 现在我不知道这个小王在哪个库的哪个表里。

[永生天地]

搜索关键字的查询

http://blog.csdn.net/xys_777/archive/2010/07/02/5708217.aspx

[claro]

从所有表及所有库中搜索关键字
-- 1 简单查询，在所有表中搜索关键字


declare @str varchar(100)
set @str='a'  --要搜索的字符串

declare @s varchar(8000)
declare tb cursor local for
    select 'if exists(select 1 from ['+b.name+'] where ['+a.name+'] like ''%'+@str+'%'')
        print '' ['+b.name+'].['+a.name+']'''
    from syscolumns a join sysobjects b on a.id=b.id
    where b.xtype='U' and a.status>=0
        and a.xusertype in(175,239,231,167)
open tb
fetch next from tb into @s
while @@fetch_status=0
begin
    exec(@s)
    fetch next from tb into @s
end
close tb
deallocate tb
-- 2 结合上面 从所有库中搜索

if object_id('up_ValueSearch')is not null drop proc up_ValueSearch
go
create proc up_ValueSearch @db varchar(200),@str varchar(100)
as
begin
declare @s varchar(8000)
declare tb cursor local for
    select 'if exists(select 1 from ['+b.name+'] where ['+a.name+'] like ''%'+@str+'%'')
        print '' ['+@db+']..['+b.name+'].['+a.name+']'''
    from syscolumns a join sysobjects b on a.id=b.id
    where b.xtype='U' and a.status>=0
        and a.xusertype in(175,239,231,167)
open tb
fetch next from tb into @s
while @@fetch_status=0
begin
    exec(@s)
    fetch next from tb into @s
end
close tb
deallocate tb
end
go
--调用示例
sp_msforeachdb 'up_ValueSearch ?,''aa'''


其他整理

------------------第一种方法----------------------

CREATE PROC sp_ValueSearch
@value sql_variant,  --要搜索的数据
@precision bit=1     --1=仅根据sql_variant中的数据类型查找对应类型的数据列.<>1,查询兼容的所有列,字符数据使用like匹配
AS
SET NOCOUNT ON
IF @value IS NULL RETURN

--数据类型处理
SELECT xtype INTO #t FROM systypes
WHERE name=SQL_VARIANT_PROPERTY(@value,N'BaseType')

--扩展数据类型及查询处理语句
DECLARE @sql nvarchar(4000),@sql1 nvarchar(4000)
IF @precision=1
    SET @sql=CASE SQL_VARIANT_PROPERTY(@value,N'BaseType')
        WHEN N'text' THEN N' LIKE N''%''+CAST(@value as varchar(8000))+''%'''
        WHEN N'ntext' THEN N' LIKE ''%''+CAST(@value as nvarchar(4000))+''%'''
        ELSE N'=@value' END
ELSE
BEGIN
    SET @sql=CAST(SQL_VARIANT_PROPERTY(@value,N'BaseType') as sysname)
    IF @sql LIKE N'%char' or @sql LIKE N'%text'
    BEGIN
        INSERT #t SELECT xtype FROM systypes
        WHERE name LIKE N'%char' or name LIKE N'%text'
        SELECT @sql=N' LIKE N''%''+CAST(@value as '
            +CASE
                WHEN LEFT(@sql,1)=N'n' THEN ' nvarchar(4000)'
                ELSE 'varchar(8000)' END
            +N')+N''%'''
    END
    ELSE IF @sql LIKE N'%datetime'
    BEGIN
        INSERT #t SELECT xtype FROM systypes
        WHERE name LIKE N'%datetime'
        SET @sql=N'=@value'   
    END
    ELSE IF @sql LIKE N'%int'
        OR @sql LIKE N'%money'
        OR @sql IN(N'real',N'float',N'decimal',N'numeric')
    BEGIN
        INSERT #t SELECT xtype FROM systypes
        WHERE name LIKE N'%int'
            OR name LIKE N'%money'
            OR name IN(N'real',N'float',N'decimal')
        SET @sql=N'=@value'   
    END
    ELSE
        SET @sql=N'=@value'
END
--保存结果的临时表
CREATE TABLE #(TableName sysname,FieldName sysname,Type sysname,SQL nvarchar(4000))

DECLARE tb CURSOR LOCAL
FOR
SELECT N'SELECT * FROM '
    +QUOTENAME(USER_NAME(o.uid))
    +N'.'+QUOTENAME(o.name)
    +N' WHERE '+QUOTENAME(c.name)
    +@sql,
    N'INSERT # VALUES(N'+QUOTENAME(o.name,N'''')
    +N',N'+QUOTENAME(c.name,N'''')
    +N',N'+QUOTENAME(QUOTENAME(t.name)+CASE
        WHEN t.name IN (N'decimal',N'numeric')
        THEN N'('+CAST(c.prec as varchar)+N','+CAST(c.scale as varchar)+N')'
        WHEN t.name=N'float'
            OR t.name like N'%char'
            OR t.name like N'%binary'
        THEN N'('+CAST(c.prec as varchar)+N')'
        ELSE N'' END,N'''')
    +N',@sql)'
FROM sysobjects o,syscolumns c,systypes t,#t tt
WHERE o.id=c.id
    AND c.xusertype=t.xusertype
    AND t.xtype=tt.xtype
    AND OBJECTPROPERTY(o.id,N'IsUserTable')=1

OPEN tb
FETCH tb INTO @sql,@sql1
WHILE @@FETCH_STATUS=0
BEGIN
    SET @sql1=N'IF EXISTS('+@sql+N') '+@sql1
    EXEC sp_executesql @sql1,N'@value sql_variant,@sql nvarchar(4000)',@value,@sql
    FETCH tb INTO @sql,@sql1
END
CLOSE tb
DEALLOCATE tb
SELECT * FROM #

exec sp_ValueSearch '要搜索的值',1 --1或不输入（即默认值1）精确匹配
exec sp_ValueSearch '要搜索的值',0 --不等于1，模糊匹配

---------------第二种方法------------------

Create   PROC xb_GetTableNameAndColNameForValue
 @value varchar(200)
AS
--求test库中包含值为@value的表和列名

--存储表名和列名
IF object_id('tabss') IS NOT NULL
 exec('drop table tabss')
CREATE TABLE Tabss(id int identity(1,1),tabname varchar(100),colName varchar(100))

--查询某表某列是否包含某个值
IF object_id('ysgs') IS NOT NULL
 exec('drop proc ysgs')
exec('create PROC ysgs(@tab varchar(100),@col varchar(100))
AS
exec(''select 1 from ''+@tab+'' where ''+@col+'' like ''''%'+@value+'%'''''')')

--将结果存入tabss表中
EXEC master.dbo.xp_execresultset 'SELECT ''exec ysgs ''''''+object_name(id)+'''''',''''''+name+'''''';if @@rowcount>0  insert tabss (colname,tabname)values(''''''+name+'''''',''''''+object_name(id)+'''''')'' FROM syscolumns s WHERE xtype in(SELECT xtype FROM systypes s2 WHERE name in(''char'',''varchar'',''nchar'',''nvarchar''))
AND id in(SELECT id FROM sysobjects s2 WHERE xtype=''u'')',N'test'


GO


/*调用
exec xb_GetTableNameAndColNameForValue 'aa_1'
SELECT * FROM tabss
*/

------------------------第三种方法---------------------
declare @name nvarchar(100)
declare cur cursor for select name from sysobjects where type = 'U'
open cur
fetch next from cur into @name
WHILE @@FETCH_STATUS = 0
begin

    declare @sql nvarchar(500),@s varchar(500)
    set @s =''
    set @sql='select @s=isnull(@s+''+'','''')+'''''',''''''+''+cast(''+name+'' as varchar)'' from syscolumns where id=object_id('''+@name+''') and xtype in(175,239,99,231,35,167) '
    exec sp_executesql @sql,N'@s varchar(500) out',@s out
    if len(@s) > 0
        exec ('if exists(select 1 from (select '+ @s+' as col from ['+@name+']) b where charindex(''aa'',col)>0) print '''+@name+'''')
    fetch next from cur into @name
end
close cur
DEALLOCATE cur

------第4种方法---------（来自小梁）

CREATE TABLE tb(id int,col varchar(20))
CREATE TABLE tb2(id int,data varchar(20))

INSERT tb VALUES(1,'中国');
INSERT tb VALUES(2,'liangck')

INSERT tb2 VALUES(1,'China')
GO

CREATE PROCEDURE dbo.FindString
    @string NVARCHAR(100)
AS

    DECLARE @SQL NVARCHAR(4000);
    SET @SQL = N'
            DECLARE @str NVARCHAR(4000);
            SELECT
                @str = ISNULL(@str + N'' OR '' + c.name + N'' LIKE N''''%'
                                                + @string + ' %'''''',
                               c.name + N'' LIKE N''''%' + @string +'%'''''') FROM syscolumns AS c JOIN systypes AS t ON c.id=OBJECT_ID(''?'')
                AND c.xtype=t.xtype
                AND t.name IN(''varchar'',''char'',''nvarchar'',''nchar'');

            SET @str = ''SELECT TOP 1 1 FROM ? WHERE ''+@str;
            CREATE TABLE #tb(a int);
            INSERT #tb(a) EXEC(@str);
            IF EXISTS(SELECT * FROM #tb)
                PRINT ''?''
        ';
    EXEC sp_MsforeachTable @SQL;
GO

EXEC dbo.FindString N'中国'

GO
DROP PROCEDURE dbo.FindString
DROP TABLE tb,tb2
--摘自http://blog.csdn.net/xys_777/archive/2010/07/02/5708217.aspx